We have demonstrated that monoclonal antibodies can be used to detect alterations in lymphocytes subsets in autoimmune diseases. In the next year, we will extend these studies by performing prospective studies that correlate alterations in lymphocyte subsets with other clinical and laboratory features. We will continue to concentrate on rheumatoid arthritis and Sjogren's Syndrome. In addition to peripheral blood and synovial fluid, we will also use monoclonal antibodies to stain frozen tissue sections. In this manner, we will be able to study the characteristics of lymphocytes at the site of inflammation, as well as those in peripheral blood. We will continue our work on comparing the peptide maps of antigens detected by monoclonal antibodies. We are currently involved in studying the SC1 antigen (a 67,000 dalton molecule on T-cells) and SC2 antigen (an Ia-like molecule) on both normal and neoplastic cells. Next, we will extend our work to additional antigens (defined by other monoclonal antibodies) found primarily on both normal and neoplastic cells to determine if oncogenic transformation leads to significant alteration of these molecules. In collaboration with Drs. Fong and Tsoukas in our laboratory, functional studies on lymphocytes from normals and disease states will be performed to further characterize T-cell and B-cell subsets.